Results of antiretroviral treatment interruption and intensification in advanced multi-drug resistant HIV infection from the OPTIMA trial

A Qualitative Scoping Review of Early-Terminated Clinical Trials Sponsored by the Department of Veterans Affairs Cooperative Studies Program From 2010 to 2020

Increasing attention has been paid to the risks and benefits of terminating large clinical trials before reaching prespecified targets, because such decisions can greatly affect the implementation of findings. The Department of Veterans Affairs (VA) Cooperative Studies Program (CSP) is a research infrastructure dedicated to conducting high-quality clinical research. A scoping review was performed to characterize barriers preventing the attainment of prespecified recruitment, statistical power, or sample-size targets in VA CSP trials. A trial was eligible for inclusion if the trial was sponsored by the VA CSP, primary findings were published within the last 10 years, and a decision was made to terminate enrollment or follow-up before meeting a priori recruitment or endpoint targets. In 11 of 29 included trials (37.9%), a decision was made to terminate the trial early. The most common reason for early termination was related to under-recruitment (n = 5). Other reasons included early detection of safety signals (n = 2), futility (n = 1), and benefit (n = 1). This review highlights recruitment as a critical facet of trial conduct that may hinder the production of high-quality data and thus warrant additional attention. Solutions to enhance recruitment now implemented by the VA CSP, including dedicated enrollment infrastructure and screening facilitated by informatics approaches, show promise in reducing this cause for early termination.

Analysis of the Impact of Antiretroviral Drug Changes on Survival of Patients with Advanced-Stage AIDS with Multidrug-Resistant HIV Infection

Objectives:

This article aims to elucidate the relationship between antiretroviral (ARV) medication changes and all-cause mortality using a total of 368 patients recruited from the United States (78%), United Kingdom (11%), and Canada (11%).

Methods:

Data sources included demographic characteristics, ARV treatment history and modifications, and clinical biomarker data from the completed OPTions In Management with Antiretrovirals clinical trial. Descriptive analysis and graphical trajectory representation of ARV drug modifications and biomarker changes were undertaken. Three hypotheses aimed at assessing the impact of ARV modification parameters on clinical outcomes were tested. Kaplan-Meier survival techniques as well as Cox proportional hazard regression models were employed.

Results:

Results from the analyses suggest that (1) switching therapy strategy from an intensified ARV regimen to a less intense one or vice versa, (2) having a moderate number (up to 2) of ARV drug changes per 6 months, and (3) changes based on clinical/HIV-related reasons or nonclinical reasons compared to ARV drug regimen changes due to clinical non-HIV reasons improved survival.

Conclusion:

Modifications in the ARV regimens of HIV-infected patients with multidrug resistance are associated with improved survival.

Estimating HIV Management and Comorbidity Costs Among Aging HIV Patients in the United States: A Systematic Review

BACKGROUND

As life expectancy of patients infected with human immunodeficiency virus (HIV) approaches that of the general population, the composition of HIV management costs is likely to change.

OBJECTIVES

To (a) review treatment and disease management costs in HIV, including costs of adverse events (AEs) related to antiretroviral therapy (ART) and long-term toxicities, and (b) explore the evolving cost drivers.

METHODS

A targeted literature review between January 2012 and November 2017 was conducted using PubMed and major conferences. Articles reporting U.S. costs of HIV management, acquired immunodeficiency syndrome (AIDS)-defining events, end of life care, and ART-associated comorbidities such as cardiovascular disease (CVD), chronic kidney disease (CKD), and osteoporosis were included. All costs were inflated to 2017 U.S. dollars. A Markov model-based analysis was conducted to estimate the effect of increased life expectancy on costs associated with HIV treatment and management.

RESULTS

22 studies describing HIV costs in the United States were identified, comprising 16 cost-effectiveness analysis studies, 5 retrospective analyses of health care utilization, and 1 cost analysis in a resource-limited setting. Management costs per patient per month, including routine care costs (on/off ART), non-HIV medication, opportunistic infection prophylaxis, inpatient utilization, outpatient utilization, and emergency department utilization were reported as CD4+ cell-based health state costs ranging from $1,192 for patients with CD4 > 500 cells/mm3 to $2,873 for patients with CD4 < 50 cells/mm3. Event costs for AEs ranged from $0 for headache, pain, vomiting, and lipodystrophy to $31,545 for myocardial infarction. The mean monthly per-patient costs for CVD management, CKD management, and osteoporosis were $5,898, $6,108, and $4,365, respectively. Improvements in life expectancy, approaching that of the general population in 2018, are projected to increase ART-related and AE costs by 35.4% and comorbidity costs by 175.8% compared with estimated costs with HIV life expectancy observed in 1996.

CONCLUSIONS

This study identified and summarized holistic cost estimates appropriate for use within U.S. HIV cost-effectiveness analyses and demonstrates an increasing contribution of comorbidity outcomes, primarily associated with aging in addition to long-term treatment with ART, not typically evaluated in contemporary HIV cost-effectiveness analyses.

DISCLOSURES

This analysis was sponsored by ViiV Healthcare, which had no role in the analyses and interpretation of study results. Ward, Sugrue, Hayward, and McEwan are employees of HEOR Ltd, which received funding from ViiV Healthcare to conduct this study. Anderson is an employee of GlaxoSmithKline and holds shares in the company. Punekar and Oglesby are employees of ViiV Healthcare and hold shares in GlaxoSmithKline. Lopes was employed by ViiV Healthcare at the time of the study and holds shares in GlaxoSmithKline.

Clinical trials of antiretroviral treatment interruption in HIV-infected individuals

: Despite the benefits of antiretroviral therapy (ART) for people living with HIV, there has been a long-standing research interest in interrupting ART as a strategy to minimize adverse effects of ART as well as to test interventions aiming to achieve a degree of virological control without ART. We performed a systematic review of HIV clinical studies involving treatment interruption from 2000 to 2017 to describe the differences between treatment interruption in studies that contained and didn't contain an intervention. We assessed differences in monitoring strategies, threshold to restart ART, duration and adverse outcomes of treatment interruption, and factors aimed at minimizing transmission. We found that treatment interruption has been incorporated into 159 clinical studies since 2000 and is increasingly being included in trials to assess the efficacy of interventions to achieve sustained virological remission off ART. Great heterogeneity was noted in immunological, virological and clinical monitoring strategies, as well as in thresholds to recommence ART. Treatment interruption in recent intervention studies were more closely monitored, had more conservative thresholds to restart ART and had a shorter treatment interruption duration, compared with older treatment interruption studies that didn't include an intervention.

A joint model for recurrent events and a semi-competing risk in the presence of multi-level clustering

Clinical trial designs often include multiple levels of clustering in which patients are nested within clinical sites and recurrent outcomes are nested within patients who may also experience a semi-competing risk. Traditional survival methods that analyze these processes separately may lead to erroneous inferences as they ignore possible dependencies. To account for the association between recurrent events and a semi-competing risk in the presence of two levels of clustering, we developed a semi-parametric joint model. The Gaussian quadrature with a piecewise constant baseline hazard was used to estimate the unspecified baseline hazards and the likelihood. Simulations showed that the proposed joint model has good statistical properties (i.e. <5% bias and 95% coverage) compared to the shared frailty and joint frailty models when informative censoring and multiple levels of clustering were present. The proposed method was applied to data from an AIDS clinical trial to investigate the impact of antiretroviral treatment on recurrent AIDS-defining events in the presence of a semi-competing risk of death and multi-level clustering and showed a significant dependency between AIDS-defining events and death at the patient level but not at the clinic level.

A joint frailty model provides for risk stratification of human immunodeficiency virus-infected patients based on unobserved heterogeneity

OBJECTIVES

To investigate the association between recurrent AIDS-defining events and a semicompeting risk of death in patients with advanced, multidrug-resistant human immunodeficiency virus infection and to identify individuals at increased risk for these events using a joint frailty model.

STUDY DESIGN AND SETTING

Three hundred sixty-eight patients with antiretroviral treatment failure in the Options in Management of Antiretrovirals Trial randomized to two antiretroviral treatment strategies using a 2 × 2 factorial design, intensive vs. standard and interruption vs. continuation, and followed for development of AIDS-defining events and death.

RESULTS

Participants were heterogeneous for risk of AIDS-defining events and death (P < 0.001), and AIDS-defining events were strongly associated with death (P < 0.001), irrespective of treatment. The frailty model was used to classify individuals into high- and low-risk groups based on unobserved heterogeneity. Low-risk individuals were unlikely to die (0%) or have an AIDS-defining event (<4%), whereas high-risk individuals had event rates approaching 70%. About one-third of high-risk individuals had accelerated mortality, all who died before experiencing an AIDS-defining event. High-risk was associated with being immunocompromised and higher predicted 5-year mortality.

CONCLUSION

The joint frailty model permits classification of individuals into risk groups based on unobserved heterogeneity that may be identifiable based on observed covariates, providing advantages over the traditional Cox model.

Distribution-Weighted Cost-Effectiveness Analysis Using Lifetime Health Loss

BACKGROUND

It is widely acknowledged that concerns for the worse off need to be integrated with the concern for cost effectiveness in priority setting, and several countries are seeking to do so. In Norway, a comprehensive framework for priority setting was recently proposed to specify the worse off in terms of lifetime loss of quality-adjusted life-years (QALYs). However, few studies have shown how to calculate such health losses, how to integrate health loss into cost-effectiveness analyses (CEAs) and how such integration impacts the incremental cost-effectiveness ratios (ICERs). The aim of this study was to do so.

METHODS

The proposed framework was applied to data from 15 recent economic evaluations of drugs. Available data were used to calculate the lifetime health loss of the target groups, and the proposed marginal weighting function was employed to adjust standard ICERs according to the size of this loss. Standard and weighted ICERs were compared to a threshold of US$35,000 per QALY gained.

RESULTS

Lifetime health loss can be calculated with the use of available data and integrated by a marginal weighting function with CEAs. Such integration affected standard ICERs to a varying degree and changed the number of interventions considered cost effective from three to eight.

CONCLUSION

Calculation of lifetime health loss and its integration with CEA is feasible and can influence the reimbursement and ranking of interventions. To facilitate regular integration, guidelines for economic evaluations could require (i) adjustment according to distributional concerns and (ii) that data on health loss are extracted directly from the models and reported. Generic databases on health loss could be developed alongside such efforts.

Mapping MOS-HIV to HUI3 and EQ-5D-3L in Patients With HIV

Objectives: The Medical Outcomes Study HIV Health Survey (MOS-HIV) is frequently used in HIV clinical trials; however, scores generated from the MOS-HIV are not suited for cost-effectiveness analyses as they do not assign utility values to health states. Our objective was to estimate and externally validate several mapping algorithms to predict Health Utilities Index Mark 3 (HUI3) and EQ-5D-3L utility values from the MOS-HIV. Methods: We developed and validated mapping algorithms using data from two HIV clinical trials. Data from the first trial (n = 367) formed the estimation data set for the HUI3 (4,610 observations) and EQ-5D-3L (4,662 observations) mapping algorithms; data from the second trial (n = 168) formed the HUI3 (1,135 observations) and EQ-5D-3L (1,152 observations) external validation data set. We compared ordinary least squares (OLS) models of increasing complexity with the more flexible two-part, beta regression, and finite mixture models. We assessed model performance using mean absolute error (MAE) and mean squared error (MSE). Results: The OLS model that used MOS-HIV dimension scores along with squared terms gave the best HUI3 predictions (mean observed 0.84; mean predicted 0.80; MAE 0.0961); the finite mixture model gave the best EQ-5D-3L predictions (mean observed 0.90; mean predicted 0.88; MAE 0.0567). All models produced higher prediction errors at the lower end of the HUI3 and EQ-5D-3L score ranges (<0.40). Conclusions: The proposed mapping algorithms can be used to predict HUI3 and EQ-5D-3L utility values from the MOS-HIV, although greater error may pose a problem in samples where a substantial proportion of patients are in poor health. These algorithms may be useful for estimating utility values from the MOS-HIV for cost-effectiveness studies when HUI3 or EQ-5D-3L data are not available.

The VACS index accurately predicts mortality and treatment response among multi-drug resistant HIV infected patients participating in the options in management with antiretrovirals (OPTIMA) study

Objectives

The VACS Index is highly predictive of all-cause mortality among HIV infected individuals within the first few years of combination antiretroviral therapy (cART). However, its accuracy among highly treatment experienced individuals and its responsiveness to treatment interventions have yet to be evaluated. We compared the accuracy and responsiveness of the VACS Index with a Restricted Index of age and traditional HIV biomarkers among patients enrolled in the OPTIMA study.

Methods

Using data from 324/339 (96%) patients in OPTIMA, we evaluated associations between indices and mortality using Kaplan-Meier estimates, proportional hazards models, Harrel’s C-statistic and net reclassification improvement (NRI). We also determined the association between study interventions and risk scores over time, and change in score and mortality.

Results

Both the Restricted Index (c = 0.70) and VACS Index (c = 0.74) predicted mortality from baseline, but discrimination was improved with the VACS Index (NRI = 23%). Change in score from baseline to 48 weeks was more strongly associated with survival for the VACS Index than the Restricted Index with respective hazard ratios of 0.26 (95% CI 0.14–0.49) and 0.39(95% CI 0.22–0.70) among the 25% most improved scores, and 2.08 (95% CI 1.27–3.38) and 1.51 (95%CI 0.90–2.53) for the 25% least improved scores.

Conclusions

The VACS Index predicts all-cause mortality more accurately among multi-drug resistant, treatment experienced individuals and is more responsive to changes in risk associated with treatment intervention than an index restricted to age and HIV biomarkers. The VACS Index holds promise as an intermediate outcome for intervention research.

Cost-effectiveness of newer antiretroviral drugs in treatment-experienced patients with multidrug-resistant HIV disease

OBJECTIVE

Newer antiretroviral drugs provide substantial benefits but are expensive. The cost-effectiveness of using antiretroviral drugs in combination for patients with multidrug-resistant HIV disease was determined.

DESIGN

A cohort state-transition model was built representing treatment-experienced patients with low CD4 counts, high viral load levels, and multidrug-resistant virus. The effectiveness of newer drugs (those approved in 2005 or later) was estimated from published randomized trials. Other parameters were estimated from a randomized trial and from the literature. The model had a lifetime time horizon and used the perspective of an ideal insurer in the United States. The interventions were combination antiretroviral therapy, consisting of 2 newer drugs and 1 conventional drug, compared with 3 conventional drugs. Outcome measures were life-years, quality-adjusted life-years (QALYs), costs, and incremental cost-effectiveness.

RESULTS

Substituting newer antiretroviral drugs increased expected survival by 3.9 years in advanced HIV disease. The incremental cost-effectiveness ratio of newer, compared with conventional, antiretroviral drugs was $75,556/QALY gained. Sensitivity analyses showed that substituting only one newer antiretroviral drug cost $54,559 to $68,732/QALY, depending on assumptions about efficacy. Substituting 3 newer drugs cost $105,956 to $117,477/QALY. Cost-effectiveness ratios were higher if conventional drugs were not discontinued.

CONCLUSIONS

In treatment-experienced patients with advanced HIV disease, use of newer antiretroviral agents can be cost-effective, given a cost-effectiveness threshold in the range of $50,000 to $75,000 per QALY gained. Newer antiretroviral agents should be used in carefully selected patients for whom less expensive options are clearly inferior.

GBV-C viremia and clinical events in advanced HIV infection

GB Virus C (GBV-C) is a non-pathogenic flavivirus, commonly found in HIV infected patients. Studies suggest a survival benefit of GBV-C viremia in HIV infection. Impact of GBV-C viremia was evaluated on clinical outcome in multidrug-resistant HIV. The OPTIMA study enrolled advanced multidrug-resistant HIV patients with a CD4 count ≤300 cells/mm(3). This study included a subset of OPTIMA patients. Primary endpoints included AIDS events or death. GBV-C status was assessed at baseline and last time point on study by real-time PCR. Cox proportional hazards models were used to determine if CD4 count (</>100/mm(3)), treatment assignment, presence or disappearance of GBV-C viremia, GBV-C viral load level and Hepatitis C virus antibody status were associated with outcome. Of 288 patients (98% male, baseline mean age 48 years, HIV viral load 4.67 log10/ml, and CD4 127 cells/mm(3)), 62 (21.5%) had detectable GBV-C viremia. The mortality rate for GBV-C infected subjects was lower, 19/62 (30.7%) versus 87/226 (38.5%), and time to death shorter (HR 0.67, 95% CI 0.41-1.11), but the results were not significantly different. The time to development of AIDS events was not different (HR 0.90, 95% CI 0.52-1.53). Among covariates, only CD4 count (HR 0.28, CI 0.19-0.42) had a significant survival effect. A trend in decreased mortality was seen in GBV-C+ patients with CD4 <100/mm(3) in multivariate analyses. GBV-C co-infection in multidrug-resistant HIV infected patients was associated with a trend in improved survival but not decreased AIDS events. Analysis was limited by cohort size.

Predictive value of HIV-1 replication capacity and phenotypic susceptibility scores in antiretroviral treatment-experienced patients

OBJECTIVES

The aim of the study was to determine the prognostic value of HIV replication capacity (RC) for subsequent antiretroviral (ARV) treatment response in ARV-experienced patients.

METHODS

RC and phenotypic resistance testing were performed at baseline and week 12 on plasma samples from patients randomized to undergo a 12-week ARV drug-free period (ARDFP) or initiate immediate salvage therapy (no-ARDFP group) in the Options in Management with Antiretrovirals (OPTIMA) trial. Dichotomous and incremental phenotypic susceptibility scores (dPSSs and iPSSs, respectively) were calculated. The predictive value of RC and PSS for ARV therapy response and/or ARDFP was evaluated using multivariate regression analysis and Pearson correlations.

RESULTS

In 146 no-ARDFP subjects, baseline RC (50.8%) did not change at week 12 and was not correlated with CD4 cell count or viral load changes at week 12 (P=0.33 and P=0.79, respectively) or at week 24 (P=0.96 and P=0.14, respectively). dPSS predicted virological but not CD4 cell count response to ARV therapy at weeks 12, 24 and 48 (P=0.002, P<0.001 and P=0.005, respectively). RC was significantly correlated with dPSS and iPSS at baseline, but did not increase their predictive value. In the 137 ARDFP patients, RC increased significantly (from 52.4 to 85.8%), but did not predict CD4 cell count and viral load changes during ARDFP (P=0.92 and P=0.26, respectively). RC after ARDFP did not predict subsequent CD4 cell count and viral load changes 12 weeks following ARV treatment reinitiation (P=0.90 and P=0.29, respectively).

CONCLUSIONS

We found no additional predictive value of replication capacity for virological or immunological responses (above what PSS provides) in patients undergoing salvage ARV treatment.

Effect of Treatment Interruption and Intensification of Antiretroviral Therapy on Health-Related Quality of Life in Patients with Advanced HIV

Background. The effect of antiretroviral therapy (ART) interruption or intensification on health-related quality of life (HRQoL) in advanced HIV patients is unknown. Objective. To assess the impact of temporary treatment interruption and intensification of ART on HRQoL. Design. A 2 x 2 factorial open label randomized controlled trial. Setting. Hospitals in the United States, Canada, and the United Kingdom. Patients. Multidrug resistant (MDR) HIV patients. Intervention. Patients were randomized to receive a 12-wk interruption or not, and ART intensification or standard ART. Measurements. The Health Utilities Index (HUI3), EQ-5D, standard gamble (SG), time tradeoff (TTO), visual analog scale (VAS), and the Medical Outcomes Study HIV Health Survey (MOS-HIV). Results. There were no significant differences in HRQoL among the four groups during follow-up; however, there was a temporary significant decline in HRQoL on some measures within the interruption group during interruption (HUI3 −0.05, P = 0.03; VAS −5.9, P = 0.002; physical health summary −2.9, P = 0.001; mental health summary −1.9, P = 0.02). Scores declined slightly overall during follow-up. Multivariate analysis showed significantly lower HRQoL associated with some clinical events. Limitations. The results may not apply to HIV patients who have not experienced multiple treatment failures or who have not developed MDR HIV. Conclusions. Temporary ART interruption and ART intensification provided neither superior nor inferior HRQoL compared with no interruption and standard ART. Among surviving patients, HRQoL scores declined only slightly over years of follow-up in this advanced HIV cohort; however, approximately one-third of patients died during the trial follow up. Lower HRQoL was associated with adverse clinical events.